Transcript for Two Drug Related Deaths Force NYC Music Festival to Shut Down

Now to the rise of the popular and potent drug believed to be responsible for two deaths at a major music festival this weekend. It forced the festival to shut down and raised a lot of questions right now. Abc's bianna golodryga is back with more on that, bianna, this is about a new designer drug. A lot of people are talking about this, amy. The deaths are bringing fresh attention to molly, what is supposed to be a pure version of extcstasy which has become the drug of the moment. Molly is in not only with kids who like dance music but 30 and 40-something professionals. For some attracted to the flashing lights and throbbing beats at the electric zoo festival in new york city, the designer drug molly may have seemed like the perfect accompaniment but this morning after two deaths and four others being hospitalized at the festival the rapid rise of this new drug is now under the microscope. On sunday festival organizers agreed to cancel the final day of the weekend-long event. At the house of blues another person died and two others hospitalized. Apparently after the use of molly. They believe it's not harmful or addictive and that there really wouldn't be any adverse side effects. Reporter: Mdma or molly as it's known in the trendy club dance scene has become the hot drug of the moment seemingly embraced by big name celebrities and embraced in song. Miley cyrus caused a stir with those lyrics in "we can't stop." When asked if she was singing about the drug she told a british newspaper "if you know what I'm talking about then you know." Even 55-year-old madonna made waves last year at a music festival in miami after asking her audience -- how many people in this crowd have seen molly? She later claimed she was referring to a song, not the drug. Molly short for molecule is a highly potent powdered form of mdma one ingredient used in ecstasy pills of it is not physically addictive making it socially acceptable to club kids to yuppies but experts say it's not only not pure, it's dangerous. They don't know what's in it. They don't know how much to use. It's such a big risk. Reporter: But now after three high-profile deaths in under two weeks, this morning many are asking if a drug many thought of as designer may also be deadly. And interestingly enough this drug was discovered in 1914 and it was used as a diet drug and of course now it's being used for all the wrong reasons and the conversation parents should have with their kids now. Especially in light of this tragedy.

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